Although the role of gut microbiota in type 2 diabetes and the
therapeutic effects of metformin have recently been reported [1-
3], the intestinal microbiota composition may be also influenced
by obesity. Microbiota depletion by antibiotic treatment
promotes browning of white adipose tissue and improves insulin
sensitivity in obese animals such as ob/ob mice and diet-induced
obesity [4]. Such metabolic improvements are mediated by
eosinophil infiltration, enriched type 2 cytokine signaling and M2
macrophage polarization in the subcutaneous white fat depots
[4]. Microbiota composition may therefore influence insulin
sensitivity.